1. Field of the Invention
This invention relates to medical needle apparatus of a non-reusable type. More specifically, it concerns syringes and phlebotomy systems that self-destruct after a single use.
2. Description of the Prior Art
The repeated use of medical needles without proper sterilization spreads many diseases including AIDS and hepatitis. Sterilization done properly requires special equipment. It is time-consuming and it can be expensive. Thus, disposable needles are frequently used.
Such syringes are increasingly documented as causing transmission of lethal diseases through accidental needle-stick injuries to administering medical personnel, laundry workers and garbage handlers. The Occupational Safety and Health Administration (OSHA) Division of the U.S. Dept. of Labor views the problem of needle-stick injuries and used syringe disposal in medical facilities substantial enough to warrant implementation of Rule 29 CFR Part 1910 which, in part, will govern approved types and use of various needle apparatus. Additionally, the World Health Organization (WHO) has gathered data concerning the incidence of disease transmission from patient to patient through the re-use of injection syringes by medical personnel in developing countries; the transmission of such lethal diseases is also well documented among the drug abuse culture in the U.S. and other developed countries. Syringe re-use in these developing countries is caused in part by the lack of available medical personnel training, and by depressed economies which support the use of reduced quantities of needed syringes, implying the re-usability of the devices. Re-use of syringes in developed countries result from use of syringes which lack single use features, or which have single-use features which may be circumvented by the user, thus allowing re-use.
Prior art has shown various attempts to satisfy the needs of the medical community through means to retract the needle following use. (Within the context of this description, "retractable" implies non-reusable since retraction disables the injection hydraulic means.) These devices usually allow the medical worker to retract the needle to the interior cavity of the syringe barrel by locking the piston to the needle hub and pulling backward until the needle is no longer exposed to cause needle-stick injuries. Recent art has shown slidable sheaths which advance forward over the exposed needle for the same reason. The devices call for the use of two hands to activate the sheath or retraction and special training to allow proficiency with the device. In the post-sheathing or post-retraction state, the syringes are longitudinally longer than the post injection state which is not desirable for disposal. The single-use attributes of retractable devices may be voluntarily circumventable, and may in fact be re-used if the retraction is not actuated.
Further, prior art has taught of means to render syringes non-reusable following a single use. These single-use devices have means to lock the piston in the syringe barrel following injection. The WHO has specific guide-lines calling for non-circumventable single-use devices; devices not requiring special training to use, and immediate actuation of the non reusable mechanism which occurs involuntarily upon beginning the injection, and very low cost of production. Prior art accomplishes certain combinations of the WHO criteria through various means, but no known prior art teaches a device which satisfactorily accomplishes all of the aforementioned criteria in a singular design.
There is a need for medical needles that can be disposed of with minimum risk to health care workers and garbage handlers. There is further need for a non-circumventable, self-destruct system for preventing re-use. Preferably, the self-destruction should be actuated immediately following, or simultaneously with fluid transfer with continued thumb pressure on an operating member in the same manner as the fluid transfer was actuated. This enables single hand operation for both fluid transfer and self-destruction. There is a further need of syringes and phlebotomy systems with a minimum number of parts and assembly so as to be extremely cost effective promoting widespread distribution and use.
Various non-reusable medical needle devices are known. Needle retraction by pulling backward on a plunger is shown in U.S. Pat. No. 4,026,287 that issued May 31, 1977 to Haller; U.S. Pat. No. 4,507,117 that issued Mar. 26, 1985 to Vining et al.; U.S. Pat. No. 4,592,744 that issued June 3, 1986 to Jagger et al.; U.S. Pat. No. 4,650,468 that issued Mar. 17, 1987 to Jennings Jr.; U.S. Pat. No. 4,675,005 that issued June 23, 1987 to De Luccia; U.S. Pat. No. 4,710,170 that issued Dec. 1, 1987 to Haber et al.; U.S. Pat. No. 4,747,829 that issued May 31, 1988 to Jacob et al.; and U.S. Pat. No. 4,747,830 that issued May 31, 1988 to Gloyer et al. U.S. Pat. No. 4,747,831 that issued May 31, 1988 to Kulli shows needle retraction by trigger release of a compressed coil spring.
Self-destruction by plugging a barrel outlet is shown by U.S. Pat. No. 4,233,975 that issued Nov. 18, 1980 to Yerman. U.S. Pat. No. 4,391,273 that issued July 5, 1983 to Chiquiar-Arias provides for a piston puncturing a wall and being retained. U.S. Pat. No. 4,687,467 that issued Aug. 18, 1987 to Cygielski provides for cutting a hole in a piston front wall. U.S. Pat. No. 4,699,614 that issued Oct. 13, 1987 to Glazier teaches detaching a piston from a shaft. U.S. Pat. No. 4,713,056 that issued Dec. 14, 1987 to Butterfield shows gripping a piston with a latching ring. French Patent No. 2,298,340 of Blanie shows impalement of a plunger on a pointed end of a barrel.